Since the OP did not write about his interactions with these sellers it is hard to know if he did or did not inform them. But I don't believe the OP was obligat

Since the OP did not write about his interactions with these sellers it is hard to know if he did or did not inform them. But I don't believe the OP was obligated in any way to tell everyone about Apple's warranty terms... so I don't think not telling them was a "dick move". I can also think of plenty of reasons why a person might know all those facts and still choose to sell the broken, still-in-warranty iPod. One of them being that you don't get a new iPod... you get a refurbished iPod and some people just don't want someone else's used stuff. Other people may have already upgraded to a new/different model and no longer need the broken one replaced.